Go development environment for Vim

The reason for creating vim-go

Go has a very versatile toolchain and commands that makes Go programming fun.
One of the famous tools is gofmt, which automatically reformats the code
according to some predefined rules. However there are many other tools like
goimports, oracle, godef, etc.. which help to provide a more productive workflow.

There are many independent vim plugins that integrate these tools into Vim. We
also have the offical Vim plugins that provides some basic Go support for Vim.
However there are many flaws with these plugins:

Gofmt destroy the undo history and it’s impossible to do undo on your code

Building, running or testing are not integrated, all of these needs additional settings.

Binary paths are hard coded

Plugins are not using the same format. Each plugin is built differently, some support lookup under the cursor, some do not.

Syntax highlighting can’t highlight functions

Auto completion needs a package and additional settings.

Many other small flaws..

The main reason to create vim-go was to integrate all these plugins, fix the
flaws and provide a common and seamless experience.

Vim-go features

Gofmt on save, keeps cursor position and doesn’t break your undo history

Go to symbol/declaration

Automatically import packages

Compile and build package

Run quickly your snippet

Run tests and see any errors in quick window

Lint your code

Advanced source analysis tool with oracle

Checking for unchecked errors.

vim-go automatically installs all necessary binaries if they are not found in
the pre-defined path ~/.vim-go (can be disabled if not desired). It comes with
pre-defined sensible settings. Under the hood it uses goimports, oracle,
godef, errcheck, gocode and golint. Let’s see how we can make use of
those tools.

Installation

vim-go is a pathogen compatible bundle. To use it just clone it into your
bundle directory:

Development with vim-go

On first usage it tries to download and install all necessary binaries.
Let’s see what commands we now can use. Below is a list of commands vim-go
supports, most of the commands are improved and new ones were introduced (some
of them are just from the official Go plugin).

vim-go uses goimports and reformats whenever you save your file. However you
have the option to disable goimports and explicitly import/drop packages:

Godoc can be called on any identifier. Just put your cursor under the
identifier and call :Godoc, it will open a new view and show the necessary documentation.

:Godoc
:Godoc <identifier>

Godef is one of my favorites tools. It’s find the source definition and jumps
to that file (go to definition). To use it just put your cursor under a
identifier and hit :Godef. It opens a new buffer (just like ctags). You might
add the following settings to your vimrc, to open the definitions in vertical,
horizontal or new tab with :

Building, testing, running are all important steps in development workflow and
should be seamless integrated. vim-go has several features that you can use. First check out the build commands:

:make
:GoBuild

:make is the default Vim command to build a project. vim-go integrates it
in way that it ** doesn’t produce ** any binary. That it is really useful
because it doesn’t pollute your work environment. Any errors are listed in a
quickfix window and can be jumped easily with default :cnext and
:cprevious. :GoBuild is similar to :make, but it creates a binary for
the given main package.

Sometimes we only have small main package that we can want to run and see the
output. For that we have:

:GoRun
:GoRun <expand>

Just calling :GoRun is going to include all files that belongs to the main
package (useful for multi file programs). To run a single file just run
:Gorun %. You can map this to a key, like <leader>r:

au Filetype go nnoremap <leader>r :GoRun %<CR>

To call go test just run:

:GoTest

Another tool we have is errcheck, which checks unchecked errors:

:GoErrCheck

Linting is useful to print out mistakes or tips about coding style. For example
if you don’t provide any documentation comment for a function golint will
warn you. To call it just execute:

:Lint

To see the dependencies of your current package run :GoDeps. If you have
multiple files you can easily see all source files (test files are excluded)
via :Gofiles.

And then we have the still experimental but powerful “oracle” tool. See the
extensive official documentation for more info: Oracle docs vim-go implements and includes the following commands (which are part of the
offical oracle vim plugin):

There are still tons of modifications and improvements one can make to this
setup. vim-go is a new project. Check it out and try it to see how it fits your
needs. Any improvements and feedback are welcome.